Photonikoptische Verbindungstechnik. Teilvorhaben: Prozessorverbindungen ueber optische Backplane-Netze Abschlussbericht

The target of the project was to investigate high bitrate (#>=#1 Gbit/s) optical interconnection networks for future high performance signal processor systems. The programme covered board-to-board interconnections and interconnections between several boards via an optical star network or an optical matrix switch. Environmental tests and system investigations should be performed using the realised demonstrators. At the beginning planar as well as fiber-optical backplane networks were considered. The realised fiberoptical demonstrators fulfilled all system demands. The constructions, however, were bulky and expensive. A planar backplane avoids these drawbacks, however, suitable low loss waveguides were lacking. In the course of the project we succeeded in reducing the attenuation of multimode polymeric stripe waveguides to the required value of 1 to 3 dB/m. With the new technology large (19'') and complex waveguide structures can be manufactured as necessary for backplane networks. For the transition from the board to the backplane we have developed a compact and connector-free solution with free space transmission and 90 beam deflection within the backplane. The free space coupling provides easy to control positioning tolerances of #+-#500 #mu#m in lateral and >20.000 #mu#m in axial direction. For board-to-board demonstrators we used at first plastic optical fibers integrated into the backplane and later on polymeric stripe waveguides, too. We have successfully demonstrated the board-to-board concept as a snap-on front-plane and as a rear-plane using standard backplane connectors. The system marigin was as high as 10 dB. Investigations concerning the feasibility of switched networks showed that only electro-optical switch matrices are useful. Using developed components and demonstrators first aging and environmental tests (temperature, humidity, dust, vibrations) have been successfully performed. In summary we have reached all relevant project goals. Decisive breakthroughs have been achieved for board-to-board coupling and in the reduction of the attenuation of polymeric stripe waveguides. Thus the feasibility of planar optical backplane networks could be demonstrated. (orig.)Available from TIB Hannover: DtF QN1(67,13) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEBundesministerium fuer Bildung, Wissenschaft, Forschung und Technologie, Bonn (Germany)DEGerman

Optische Verbindungstechnik fuer zukuenftige Signalprozessoren. T. 1 und 2 Optische Interchip- und Leiterplattenverbindungen. Laserdioden niedriger Schwelle. Abschlussbericht

For future high-speed signal processors we have developed optical chip-to-chip and optical board-to-board interconnects as well as GaAs laser diodes with low threshold currents. For optical chip-to-chip interconnects a demonstrator, distributing clock/data signals from one transmitter to four receivers, has been realized. Signal transmission between chips occurs via an optical distribution plate, which is mounted in short distance above the electrical substrate. The distribution structure was realized by ion exchange in glass and the coupling micromirrors were manufactured by photoablation; chip positioning was done by flip-chip solder bonding. Using this test systemdata distribution at 1GBit/s has been demonstrated successfully. Concerning optical board-to-board interconnects initially we were interested in free-space interconnects between neighbouring boards. For this application we have evaluated a star bus structure with optical waveguides on a backplane. GaAs lasers with low threshold currents have been realized as Fabry-Perot lasers as well as surface-emitter lasers. For Fabry-Perot lasers we have adopted the ridge-structure with single quantum well (SQW) active layers. With short cavities (#>=# 100 #mu#m) and high reflecting, slightly asymmetrical, mirrors (90%/96%) we have obtained threshold currents as low as 1.2 mA. For surface-emitters lasers best results have been achieved when using InGaAs-QW layers within the resonator. Emitters with a 10 #mu#m wide active area, which was determined by ion implantation yielded threshhold currents around 1.4 mA. The modulation bandwith of both laser types was about 5 GHz. (orig.)SIGLEAvailable from TIB Hannover: F94B1265+a / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekBundesministerium fuer Forschung und Technologie (BMFT), Bonn (Germany)DEGerman

Optische Sende- und Empfangselemente fuer den langwelligen Spektralbereich Abschlussbericht

SIGLETIB Hannover: FR 1813 / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman